Biomedical subjects

Y Aoki

Publications and source records attributed to Y Aoki.

At least 469 records · Page 26Linked to original sources

PubMed1993

[Current status and future prospects of the radiation oncology treatment planning system].

Treatment planning is the most essential radiation oncology practice and has been developing owing to various technological innovations such as faster computing speed, advanced computer graphics and enormous data storage capacity. Treatment planning consists of CT data retrieval, target input, selection of treatment techniques and dose calculation, evaluation of dose distribution, and data transfer to the accelerator, each of which has been progressing quite rapidly. In particular, ongoing topics in treatment planning include multi-leaf conformation, non-coplanar technique, CT scanner dedicated to treatment planning and data transfer through LAN. Target delineation using PACS, and megavoltage verification imaging represented by portal imaging, are also useful. Higher local control rates as well as lower complication probabilities are expected with the sophisticated treatment planning system.

Forecasting↗

PubMed1993

[In vitro antifungal activity of omoconazole nitrate, a new imidazole antimycotic].

In vitro antifungal activities of omoconazole nitrate (OMZ), a new topical imidazole antifungal agent, were studied against 364 strains of 22 genera and 47 species of stock cultures of a wide range of medically important fungi. The test was carried out using the agar dilution method with bifonazole (BFZ) as the reference drug. OMZ exhibited a broad spectrum of antifungal activities. Most of yeasts including Malassezia, dimorphic fungi, non-pigmented hyphomycetes and dermatophytes were almost equally or more greatly susceptible to OMZ than to BFZ, although the MIC values of these drugs against Candida and probably some other fungi were influenced differently by testing media. Comparable susceptibility to OMZ were observed for fresh clinical isolates of dermatophytes and Candida albicans. OMZ was also active against Malassezia. These results have encouraged us to proceed in vivo studies using animal models of cutaneous mycoses.

Antifungal Agents↗

PubMed1993

[Two unusual cases of half-sibling test with DNA polymorphism].

In usual paternity cases, the putative man and the mother-child couple are alive. However, there are some cases in which putative man and mother were deceased and only children were available for analyses. It is difficult to determine the presence or absence of half-sibling relationship from analyses of conventional blood group markers (CBGM). In this study, five kinds of single locus DNA probes were applied to 2 half-sibling cases. To decide usefulness of single locus DNA probes, we defined likelihood ratio of half-sibling (LRHS) based on the likelihood ratio of paternity (LRP) and also investigated the distribution curves of log10 LRHS in cases of unrelated combinations and half-sibling combinations. Distribution curves of log10 LRHS from DNA analyses in the cases of unrelated combinations and half-sibling combinations is more clearly separated than from CBGM. Single locus DNA probes are considered to be more informative for half-sibling cases.

Blood Group Antigens↗

PubMed1993

Medullasin levels in neutrophils of patients with pustulosis palmaris et plantaris.

Medullasin is one of the serine proteases found in human bone marrow cells. The protease in granulocytes is assumed to play an important role in the induction of chronic inflammation. We measured the medullasin levels as a parameter of neutrophil function in granulocytes from patients with pustulosis palmaris et plantaris. All 17 patients studied underwent tonsillectomies, and the changes in the amount of medullasin were followed after surgery. Seven of the 17 patients were cured during the follow-up period (average: 21 months). In all the patients in whom PPP improved, the medullasin levels decreased significantly from the period of active disease when pustules were present to the inactive period. The amount of medullasin did not fall significantly in patients whose PPP did not improve. It is concluded that medullasin levels may reflect the activity of PPP and may serve as a criterion for performing a tonsillectomy.

Adult↗

PubMed1993

[A case of spontaneous pneumothorax due to rupture of bleb infected with aspergillosis].

A 17-year-old male was diagnosed as having left spontaneous pneumothorax by chest X-ray. Chest CT scan showed a cystic shadow with a thick wall in the left apex. Thoracotomy was performed, and the bleb was resected. Histologically, aspergillus was found in the cavity and the wall of the resected bleb. In this case, we consider that focal aspergillus infection in the bleb caused spontaneous pneumothorax. In cases of spontaneous pneumothorax in which the bleb wall is thick, the bleb should be evaluated by histological and bacteriological examination. Such a case has been rarely reported in Japan.

Adolescent↗

PubMed1993

[Estimations of organ dose and health risk of the mass chest X-ray examinations in children].

In Japan, mass chest X-ray examinations are mandated by law for schoolchildren and students. Recently, questions of the justification of such X-ray examination have arisen. In this study the absorbed doses of each organ, and the health detriments from the mass chest X-ray examinations to schoolchildren and students were estimated. The doses of organs were measured by the TLDs (Mg2SiO4), slab phantom, and anthropomorphic phantom. The probability of fatal cancer, and the resultant reduction in life expectancy induced by mass chest X-ray examinations were calculated by the multiplicative risk projection model of the ICRP-1990. The absorbed doses of lung, thyroid glands, esophagus, stomach, breast, and red bone marrow in first-year elementary schoolchildren were 90, 30, 90, 60, 90, and 30 muGy, respectively, and the doses in ovaries and testes were almost nil. Each organ dose of first-year students of junior high school was about 1.5 times that for elementary schoolchildren. The total radiation-induced lifetime cancer risk of schoolchildren and students was from 0.3 x 10(-5) to 0.9 x 10(-5) per person by the multiplicative risk projection model of the ICRP-1990 and a factor of 2 for the DDREF (dose and dose rate effectiveness factor). The reduction in life expectancy by radiation induced fatal cancer was from 15 x 10(-5) years to 50 x 10(-5) years per person. The results of this study suggest that subjects of mass chest X-ray examinations should be carefully selected from the viewpoint of radiation protection.

Adolescent↗

PubMed1993

[Volume measurement of the horizontal extraocular muscles using magnetic resonance imaging].

The volume of the horizontal extraocular muscles of 11 normal adults and three patients with ophthalmoplegia was measured using magnetic resonance imaging (MRI). The MRI examinations were carried out with a Signa Advantage, 1.5 tesla superconductive magnetic system manufactured by General Electric. This method employs the spin echo technique with a 3.0 mm gapless slice, a 350 ms. repetition time, and a 17.0 ms. echo time. The MRI films were projected and magnified on Kent paper using an overhead projector. Then the shapes of the horizontal extraocular muscles were traced. The volume of the muscles was measured as the total weight of Kent papers which were cut out from muscle shapes in all the slices. The average volume of the normal medial and lateral rectus muscles was 690 +/- 87 mm3 and 734 +/- 77 mm3, respectively. Two cases with peripheral nerve palsy showed typical atrophy of the paretic muscles. A case with orbital myositis showed typical hypertrophy of the inflamed muscles. This measurement may prove useful in the analysis and evaluation of extraocular muscles, especially in ophthalmoplegia.

Adult↗

PubMed1993

[A case of extraskeletal Ewing's sarcoma of the chest wall].

A 22-year-old woman was admitted to our hospital complaining of high fever, dyspnea and wheeze. Chest X-ray film and CT scan showed a huge mass lesion in the right chest. Histological findings of specimens obtained by both needle biopsy and surgery showed necrotic tissue. She died of rapidly progressive pulmonary metastasis three months after surgery, and at autopsy, the tumor was diagnosed as extraskeletal Ewing's sarcoma originating from the chest wall.

Adult↗

PubMed1993

[Hepatic metastases from jejunal leiomyosarcoma treated effectively by repeated transarterial embolization with carboplatin].

A 67-year-old man complained of abdominal mass, abdominal pain and tarry stool. He was diagnosed as having jejunal leiomyosarcoma and multiple liver metastases after examination. The jejunal leiomyosarcoma was resected by operation. Unrectable liver metastases were repeatedly treated by transarterial embolization with carboplatin and Lipiodol, and a significant reduction was achieved. TAE with carboplatin and Lipiodol was considered evaluating efficiency therapy without side effect. He has remained well presently for 1 years 10 months after operation.

Aged↗

PubMed1993

Fast neutron therapy for malignant gliomas--results from NIRS study. National Institute of Radiological Sciences.

The results of combined radiotherapy with fast neutrons and photons for 39 malignant gliomas were analyzed. The patients consisted of 16 astrocytoma grade 3 and 23 glioblastoma multiforme. There were two kinds of combination methods which were either "boost therapy" or "mixed beam therapy" with a localized fast neutron field. The average dose of fast neutrons was 569 cGy (n, gamma) and that of photons was 36.86 Gy. The median survival of astrocytoma grade 3 was 15.5 months, and that of glioblastoma multiforme was also 15.5 months. With respect to the combination methods, there was no difference between the boost regimen and the mixed beam regimen. This result seems to have no impact on survival compared to other reports. Patients' ages, surgical debulking procedures, and photon doses were listed as significant prognostic factors, but doses of fast neutrons had no prognostic significance for survival. Because there were no moderate or severe complications for the brain except permanent epilation in all cases, neutron dose escalation study with a localized field will be recommended.

Age Factors↗

PubMed1992

Topical antibiotics in cholecystectomy for gallstone diseases.

Efficacy of topical antibiotics in cholecystectomy for gallstone disease was evaluated. Forty-four patients who accepted topical single administration of 1 or 2 g each of latamoxef, cefmenoxime, cefotiam or cefamandole during operation were compared with 36 patients with systemic administration of cefem antibiotics by intravenous drip at a dose of 1 or 2 g, twice daily for postoperative 4 to 7 consecutive days. In topical administration group, concentration of each antibiotic in the gallbladder and common duct bile, gallbladder tissue, parietal peritonea and intra- and postoperative peripheral blood exceeded mostly MIC80 against bacteria usually existing in bile by biliary tract infection or bacteria by wound infection. There was no difference between the two groups in postoperative clinical course. Thus, an adequate prophylactic effect can be expected by topical use of antibiotic during cholecystectomy.

Administration, Topical↗

PubMed1992

Enzyme-linked immunosorbent assay for the detection of cathepsin-kininogen complexes in human plasma.

A simple and sensitive enzyme-linked immunosorbent assay (ELISA) for the determination of cathepsins B-, H- and L-kininogen (B-KG, H-KG, and L-KG) complexes was constructed using a microtiter plate based sandwich technique. The assay range was 7.5-480 ng/ml with three cross-linked cathepsin-kinin-free low molecular weight KG (LMWKGf) complexes. The average within-run coefficients of variation (CV) using three concentrations were 7.5, 7.2 and 9.9% for B-LMWKGf, H-LMWKGf, and L-LMWKGf complexes, respectively. The between-run CV values indicated satisfactory reproducibility for the method. Recoveries of cross-linked B-LMWKGf, H-LMWKGf, and L-LMWKGf complexes from negative control plasma were 127 +/- 7.1, 112 +/- 5.8 and 102 +/- 8.8% (n = 10, mean +/- SD), respectively, whereas the average recovery from phosphate buffer (pH 7.2) containing 0.15 M NaCl, 0.05% Tween-20 and 0.1% bovine serum albumin was 93.1 +/- 8.2% (n = 10, mean +/- SD). It was possible to detect B-KG and H-KG complexes in the plasma of 5/280 and 14/280 patients manifesting acute phase responses. Levels in plasma from healthy individuals were negligible. This ELISA should permit the study of cathepsin metabolism in acute phase disorders.

Acute-Phase Reaction↗

PubMed1992

Induction of glutathione S-transferase P-form in primary cultured rat liver parenchymal cells by co-planar polychlorinated biphenyl congeners.

Alterations in protein synthesis in primary cultured rat liver parenchymal cells were examined after their exposure to the potent carcinogens, polychlorinated biphenyl (PCB) congeners. Co-planar PCB congeners (3,4,5,3',4'-PCB and 3,4,5,3',4',5'-PCB) (10 nM) induced a protein, the Mr of which was 25,000 (25 k protein) under denaturing conditions. However, non-co-planar PCB congeners and several xenobiotics, which induce microsomal proteins, did not induce the 25 k protein. By using immunoblotting, the 25 k protein was identified as glutathione S-transferase P-form (GST-P, 7-7, EC 2.5.1.18).

Animals↗

PubMed1992

Clinical and immunological evaluation of intraoperative radiation therapy for patients with unresectable pancreatic cancer.

The clinical efficacy of intraoperative radiation therapy (IORT) and the changes of immunological parameters were investigated. Nine patients with unresectable pancreatic cancer were treated with IORT (2,500-3,500 cGy) and the changes of various immunological parameters were compared with those in 11 patients with advanced cancer who received external beam irradiation therapy (XRT), 2,500-3,500 cGy. After IORT, 71% of patients obtained pain relief, two of the nine patients showed a partial response, and the serum CA 19-9 level decreased in six patients. However, the median survival was only 210 days. Natural killer activity, lymphokine-activated killer activity, and interferon gamma-activated killer activity were not inhibited by IORT, and phytohemagglutinin-induced blastogenesis was actually augmented after IORT, whereas all these parameters were inhibited by XRT. Thus, it is suggested that IORT may augment or at least stabilize systemic antitumor immunity.

Aged↗

PubMed1992

Protective effect of vitamin E supplementation on increased thermal stability of collagen in diabetic rats.

Products similar to non-enzymatic glycation end products are known to arise from the interactions between proteins and lipid peroxides in vitro. In this study, we assessed the effect of vitamin E, which possibly modifies lipid peroxide, on advanced glycation end products or similar products in vivo by measuring the fluorescence and thermal rupture time of tail tendon collagen in streptozotocin-induced diabetic rats. The diabetic rats and non-diabetic rats were fed a vitamin E supplemented diet, and a control diet starting 3 days after the streptozotocin injection. After the 4-week treatment, the serum lipid peroxide levels expressed as thiobarbituric acid reactants in the diabetic rats on control diet (15.9 +/- 2.6 mumol/l[SEM]) were significantly (p less than 0.05) higher than in the non-diabetic rats (7.9 +/- 1.3 mumol/l on control diet and 3.3 +/- 0.4 mumol/l on supplemented diet), but the levels in the diabetic rats on supplemented diet (7.9 +/- 2.3 mumol/l) were reduced to the normal levels. No significant differences were found in serum glucose and glycated haemoglobin levels within the diabetic rats on control and supplemented diets. Both the fluorescence and thermal rupture time of collagen were significantly (p less than 0.05) increased in the diabetic rats on both diets compared with those in the corresponding non-diabetic rats. Although there was no significant difference in the collagen-linked fluorescence within the diabetic rats on control and supplemented diets, the thermal rupture time was significantly (p less than 0.01) shortened with supplemented diet (10.8 +/- 0.7 min on supplemented diet vs 15.0 +/- 0.7 min on control diet).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

Suppression of ischemia-reperfusion injury by liposomal superoxide dismutase in rats subjected to tourniquet shock.

To investigate the role of oxygen-derived free radicals in the pathogenesis of tourniquet shock, the authors present an experimental animal model. Two groups of rats were fastened with rubber tubes on both thighs (1.5 kg/cm2) for 6 h under pentobarbital anaesthesia. One group was administered liposomal superoxide dismutase (L-SOD 30,000 U/kg body weight), and the other liposome as a control 3 h prior to tourniquet removal. No rats in the control group (n = 20) survived more than 24 h after reperfusion, whereas 55% of animals treated with L-SOD (n = 20) survived for 24 h or more, and two recovered completely (P less than 0.005). Blood samples were obtained from the abdominal aorta after laparotomy of anaesthetized rats of both groups at different time intervals. Changes in the hematocrit value and blood urea nitrogen during the early periods after reperfusion were attenuated by prior administration of L-SOD, and the total plasma SOD activity of the control animals decreased promptly and continuously throughout the experimental period. This experimental model was very useful to study the pathogenesis of tourniquet shock with respect to reproducibility, induction of the shock stages and mortality. It is thought that oxygen-free radicals are involved in the induction of tourniquet shock, and L-SOD was, to a certain extent, effective against reperfusion injury in the early stages of shock.

Alanine Transaminase↗

PubMed1992

ATP-dependent strontium uptake by basolateral membrane vesicles from rat renal cortex in the absence or presence of calcium.

ATP-dependent Sr2+ transport was examined in vitro using basolateral membrane (BLM) vesicles isolated from rat renal cortex to clarify the discrimination mechanisms between strontium (Sr) and calcium (Ca) in renal tubules during reabsorption. ATP-dependent Sr2+ uptake and Ca2+ uptake were observed in renal BLM vesicles and were inhibited by vanadate. Hill plots indicate similar kinetic behavior for Ca2+ and Sr2+ uptake. The apparent Km and Vmax of ATP-dependent Sr2+ uptake were both higher than those for Ca2+ uptake. ATP-dependent Sr2+ uptake by BLM vesicles diminished in the presence of 0.1 microM Ca2+ and was more markedly inhibited by 1 microM Ca2+. Hill plots of Sr2+ uptake data with and without 0.1 microM Ca2+ showed that the cooperative behavior of Sr2+ uptake was not changed by Ca2+. In the presence of 0.1 microM Ca2+, the affinity of the transport system for Sr2+ and the velocity of Sr2+ uptake in the BLM were both decreased. However, the rate of Ca2+ uptake was not diminished by Sr2+ concentrations of less than 1.6 microM. These results suggest that Ca2+ is preferentially transported in the renal cortex BLM when Ca2+ and Sr2+ are present at the same time.

Adenosine Triphosphate↗

PubMed1992

No significant effect of vitamin E deficiency or supplementation on collagen-linked fluorescence in skin of diabetic rats.

It is speculated that oxidative stress in vivo may have some influence on advanced, nonenzymatic, glycosylation end products. However, this has not been demonstrated yet. We assessed changes in collagen-linked fluorescence in the skin of nondiabetic and streptozotocin-induced diabetic rats fed three different diets for 4 weeks that could modify oxidative stress: vitamin E-deficient (D), vitamin E-supplemented (S), and control (C). The serum lipid peroxide level expressed as thiobarbituric acid (TBA) activity in diabetic rats on the S diet (9.6 +/- 1.0 [SE] nmol/L/mL) was significantly (P less than .01) lower than that in rats on the D diet (111.4 +/- 22.4), and similar to that in nondiabetic rats on the C diet (12.4 +/- 2.2). The collagen-linked fluorescence level was significantly (P less than .01) higher in diabetic rats than in nondiabetic rats, which corresponded to the serum glucose and glycosylated hemoglobin levels. However, there were no significant differences in the fluorescence levels among three groups classified by three different diets in both nondiabetic and diabetic rats (21.7 +/- 1.7 arbitrary U/mg collagen for D, 22.3 +/- 2.0 for C, and 22.8 +/- 2.5 for S in nondiabetic rats v 41.2 +/- 4.1 for D, 40.1 +/- 4.7 for C, and 39.3 +/- 3.5 for S in diabetic rats), despite significant changes in serum lipid peroxide levels. Consequently, there were no significant changes found in collagen-linked fluorescence levels in diabetic rats wherein oxidative stress was modified by vitamin E deficiency and supplementation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗